Find A for Partial Fractions 1/(x+5)^2 (x-1)

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pillar
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1/(x+5)^2 (x-1)
B=(-1/6) C=(1/36)

I can't find the value of A, what method do you use to find it?
 
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pillar said:
1/(x+5)^2 (x-1)
B=(-1/6) C=(1/36)

I can't find the value of A, what method do you use to find it?

b]1/(x+5)^2 (x-1)[/b] = A/(x+5) + B/(x + 5)^2 + C/(x - 1)
Put x = 0.
 
pillar said:
1/(x+5)^2 (x-1)
B=(-1/6) C=(1/36)

I can't find the value of A, what method do you use to find it?

[tex]\frac{1}{(x+5)^{2}(x-1)}[/tex] will disintegrate into [tex]\frac{Ax+B}{(x+5)^{2}} + \frac{C}{x-1}[/tex]

Compare coefficients on both sides to get

A = -1/36
B = -11/36
C = 1/36
 
Ok thank, now what about this problem?

[tex]\frac{(x)^3}{(x+4)^{2}}[/tex] will disintegrate into [tex]x+4[/tex]=[tex]\frac{Ax+B}{(x+4)^{2}}[/tex]

I'm not sure where to go from there, to get the values of A & B.
 
pillar said:
Ok thank, now what about this problem?

[tex]\frac{(x)^3}{(x+4)^{2}}[/tex] will disintegrate into [tex]x+4[/tex]=[tex]\frac{Ax+B}{(x+4)^{2}}[/tex]

I'm not sure where to go from there, to get the values of A & B.

[tex]\frac{(x)^3}{(x+4)^{2}}[/tex] will disintegrate into

[tex]\frac{(x+4-4)^3}{(x+4)^2}[/tex]

which you can expand using the [tex](a+b)^3[\tex\ standard formula and then its the same as the last one. Compare coefficients of powers of x on both sides to get A,B,C and so on.[/tex]